Re: (context post by Gavin Andresen)

They key bits of code are: Code:fileout << FLATDATA(pchMessageStart) << nSize; … fileout << *this;pchMessageStart are the four magic bytes, and those are written with FLATDATA.

The CBlock itself is written by << *this, and that’s done by the IMPLEMENT_SERIALIZE in main.h: Code: IMPLEMENT_SERIALIZE ( READWRITE(this->nVersion); nVersion = this->nVersion; READWRITE(hashPrevBlock); READWRITE(hashMerkleRoot); READWRITE(nTime); READWRITE(nBits); READWRITE(nNonce);

    // ConnectBlock depends on vtx being last so it can calculate offset                                             
    if (!(nType & (SER_GETHASH|SER_BLOCKHEADERONLY)))
        READWRITE(vtx);
    else if (fRead)
        const_cast<CBlock*>(this)->vtx.clear();
)

The READWRITE macros Do The Right Thing, reading in or writing out the members in a machine-independent way.

See http://github.com/gavinandresen/bitcointools for simplified Python code that can dump out transactions and blocks.

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